Analog transcap device

A method of operating a semiconductor variable capacitor comprising a first equivalent capacitance plate and a second equivalent capacitance plate, and at least one control region, the method comprising:

• applying a control voltage between said first capacitance plate and at least one between said control region and said second capacitance plate;
• wherein the capacitance value between said first and said second capacitance plates of said semiconductor variable capacitor is varied by varying said control voltage;
• wherein said control region forms a rectifying junction with at least one of said first and second capacitance plate, and
• wherein the variation of said control voltage causes a variation of the voltage drop across said rectifying junction.

A differential semiconductor variable capacitor comprising:

• at least a first, a second and a third control region formed in a semiconductor region;
• at least a first and a second conductive region forming, respectively, a first equivalent capacitance plate and a second equivalent capacitance plate of said differential semiconductor variable capacitor;
• wherein said first, said second and said third control regions are directly coupled, respectively, to a first, a second and a third control terminals of said differential semiconductor variable capacitor;
• wherein said first and said second conductive regions are directly coupled, respectively, to a fourth and a fifth terminal of said differential semiconductor variable capacitor;
• wherein said first control region is directly coupled to said semiconductor region;
• wherein each one of said second and said third control regions forms a rectifying junction with said semiconductor region, and
• wherein the capacitance value between said fourth and fifth terminals of said differential semiconductor variable capacitor is varied by varying a control voltage applied between said first control terminal and at least two of the other terminals of said differential semiconductor variable capacitor.

A method of operating a semiconductor variable capacitor comprising at least a first, a second and a third control region formed in a semiconductor region, and at least a first and a second conductive regions forming, respectively, a first equivalent capacitance plate and a second equivalent capacitance plate of said differential semiconductor variable capacitor, the method comprising:

• applying a control voltage between said first control region and at least said second and said third control regions;
• wherein said first, said second and said third control regions are directly coupled, respectively, to a first, a second and a third control terminals of said differential semiconductor variable capacitor;
• wherein said first and said second conductive regions are directly coupled, respectively, to a fourth and a fifth terminals of said differential semiconductor variable capacitor;
• wherein said first control region is directly coupled to said semiconductor region;
• wherein each one of said second and said third control regions forms a rectifying junction with said semiconductor region, and
• wherein the capacitance value between said fourth and fifth terminals of said differential semiconductor variable capacitor is varied by varying said control voltage.